PREFACE 



This report is published to provide coastal engineers an analysis of the 

 performance of a sand trap structure and the effects of impounded sediment on 

 the structure. The work was carried out under the U.S. Army Coastal Engineer- 

 ing Research Center's (CERC) Beach-Fill Sediment Criteria work unit, Shore 

 Protection and Restoration Program, Coastal Engineering Area of Civil Works 

 Research and Development . 



The report was prepared by Dr. R.D. Uobson, Engineering Geology Branch, 

 under the general supervision of Dr. C.H. Everts, Chief, Engineering Geology 

 Branch, and Mr. N. Parker, Chief, Engineering Development Division. 



Special thanks are extended to C. Gable, who provided invaluable field and 

 logistical support during the fieldwork in California; to R. Bruno, who supplied 

 hydrosurvey data. Littoral Environment Observation (LEO) data, and data evalu- 

 ation techniques; to the Naval Facilities Command, Washington, D.C., for the 

 use of their vibratory corer; to the Commander and members of the Shops Crew 

 of the Naval Civil Engineering Laboratory, Port Eueneme, California, who 

 obtained most of the cores for this study; and finally, to E. Lagrone, U.S. 

 Army Engineer District, Mobile, who provided technical training in use of the 

 coring apparatus. 



Technical Director of CERC was Dr. Robert W. Whalin, P.E., upon publica- 

 tion of this report. 



Comments on this publication are invited. 



Approved for publication in accordance with Public Law 166, 79th Congress, 

 approved 31 July 1945, as supplemented by Public Law 172, 88th Congress, 

 approved 7 November 1963 . 



TED E. BKROP 



Colonel, Corps of Engineers 



Commander and Director 



